Amoebic dysentery is caused by
Protozoan
Entamoeba histolytica is a parasite which lives in the upper part of the large intestine and causes a disease called amoebic dysentery or amoebiasis. Early symptoms (in about one to four weeks) include loose stools and mild abdominal cramping. If the disease progresses, frequent, watery, and/or bloody stools with severe abdominal cramping (termed amoebic dysentery) may occur.